21535341115221 has 12 divisors (see below), whose sum is σ = 31119657411648. Its totient is φ = 14350869348264.

The previous prime is 21535341115219. The next prime is 21535341115237. The reversal of 21535341115221 is 12251114353512.

21535341115221 is a `hidden beast` number, since 2 + 1 + 5 + 3 + 5 + 3 + 411 + 15 + 221 = 666.

It is not a de Polignac number, because 21535341115221 - 2¹ = 21535341115219 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21535341115291) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 502038075 + ... + 502080968.

It is an arithmetic number, because the mean of its divisors is an integer number (2593304784304).

Almost surely, 2^{21535341115221} is an apocalyptic number.

It is an amenable number.

21535341115221 is a deficient number, since it is larger than the sum of its proper divisors (9584316296427).

21535341115221 is a wasteful number, since it uses less digits than its factorization.

21535341115221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1004121432 (or 1004121429 counting only the distinct ones).

The product of its digits is 36000, while the sum is 36.

Adding to 21535341115221 its reverse (12251114353512), we get a palindrome (33786455468733).

The spelling of 21535341115221 in words is "twenty-one trillion, five hundred thirty-five billion, three hundred forty-one million, one hundred fifteen thousand, two hundred twenty-one".